Need advice for a double carrier bag (2 cats including one weighing 6kg)

Hello everyone, I am looking for a double carrier bag for my two cats, and I would like your feedback or model recommendations if you have tested it.

My two cats: • A little one weighing 3.5 kg (recently adopted, still a little fragile), • And my big 6 kg cuddly toy that I've had for 8 years. They get along very well, no worries about being close during transport.

I sometimes travel by train or carpool, and I would like to have a backpack that is sturdy, comfortable and well ventilated enough to be able to carry both together, instead of having two separate bags like today.

I spotted a model on Amazon that I find super practical with the two stacked compartments. This is exactly what I'm looking for in terms of size, but I don't know if it's sturdy enough for a total of almost 10 kg, nor if it's really comfortable for them over several hours.

Any feedback? Or recommendations for similar models, not too expensive but well made?

Thanks in advance !!